The present invention relates to ultrasonic cleaning of semiconductor wafers and more particularly to a method of cleaning wafers sequentially as part of an in-line semiconductor manufacturing process.
While ultrasonic cleaning of semiconductor wafers has been proposed heretofore, such proposals have met with very limited success and acceptance by the industry. While batch cleaning in tanks has been used for some steps of semiconductor manufacturing, in-line ultrasonic cleaning of successive wafers as part of a continuous semiconductor manufacturing process has not been successfully implemented, notwithstanding some considerable experimentation.
Among the several objects of the present invention may be noted the provision of apparatus for cleaning the surface of a semiconductor wafer; the provision of such apparatus which is highly effective in thoroughly cleaning the water's surface; the provision of such apparatus which will evenly clean the entire wafer surface; the provision of such apparatus which operates quickly and reliably; the provision of such apparatus which is suitable for individually cleaning successive wafers as part of an in-line semiconductor manufacturing process; and the provision of such apparatus which is of relatively simple and inexpensive construction. Other objects and features will be in part apparent and in part pointed out hereinafter.